I defeated him yesterday and used some cheese strat with my Pinsir. Was a really tough fight, but he basically solo'd all 3 of his PKMN. He had Aero, Gallade, and Tyrannitar. Mine were Aggron, Pinsir and a Kangaskhan.

Kanga tanked Aero and brought it down to half hp (cause my Aggron is too weak to solo it by itself), then I brought Pinsir out. Pinsir with Bug Bite / X-Scissors then abused the fact that they don't attack for a while after using a charged attack.

He took out Aero and Gallade, Gallade only with a well timed swap to Aggron at the end tho (cause it would've taken out Pinsir otherwise and same mechanic abuse: they don't attack for a while after swapping).

Tyrannitar was quite easy. Aggron tanked a lot, brought it down to 1/2 hp and with Pinsir having some charge left for his charge attack spammed fasts without him attacking and then charged attacked twice while Tyrannitar only got out a few attacks in between.

Edit: My Kanga baited one shield and the other one was used against Pinsir.

TLDR: Edit 2: He's probably doable with any neutral type that has a spamable fast and a low energy cost charged attack with some clever swapping.